1. Field of the Invention
The present invention relates to a method of and a system for controlling brakes wherein a target slip ratio of each wheel can be estimated based on a vehicle deceleration prior to the start of antilock control.
2. Description of the Related Art
An antilock control system is known which is suitable for use in a motorcycle, i.e., a 2-wheeled automotive vehicle, for example. In the antilock control system, an antilocking modulator is disposed between a master cylinder for converting a brake operating instruction issued by actuating a lever and a pedal by a driver into desired hydraulic pressure and a caliper cylinder for causing brake disks of wheels to generate braking forces. A control circuit is supplied with signals indicative of front- and rear-wheel speeds. Further, a caliper pressure control signal is outputted to the modulator so as to brake each wheel, based on a computed slip ratio or both an acceleration and a deceleration of each wheel or the like.
In this case, the antilock control is started when the computed slip ratio is more than or equal to a set slip ratio. The set slip ratio normally varies depending on a vehicle speed or velocity.
Now, it is known that controllability of the vehicle is related to a ground load sharing proportion or ratio of each of the front and rear wheels and the ground load sharing ratio is correlated to a vehicle deceleration. Though it is apparent that correlation exists between the vehicle controllability and the vehicle deceleration in this way, conventional antilock control has been carried out irrespectively of the vehicle deceleration. Thus, the vehicle controllability is subject to change depending on the vehicle deceleration at the start of the antilock control.